The present invention relates generally to laundry machines. In particular, an apparatus and method reduces gaps between articles of laundry passed between two laundry stations.
In commercial laundry facilities, laundry articles, such as bed sheets, table linens, blankets, or the like, are fed into a flatwork ironer and/or automatic folder after being washed. In order to obtain neatly folded and unwrinkled laundry, the laundry articles should be presented to the ironer and/or folder with no wrinkles or folds and with the leading edge square.
One method for presenting the sheets with no folds employs operators to manually spread the sheet apart and to place the sheet in the ironer or folder by hand. However, the use of operators tends to slow the output of laundry processing equipment and can lead to inaccurate and inconsistent placement of the sheet. In addition, accurate placement of the sheet depends on the skill of the operators, so fatigued operators may increase costs.
To overcome the difficulties in using manual spreading, modern laundry facilities use automatic spreader-feeder machines. One machine of this spreader-feeder type is disclosed in U.S. Pat. No. 5,440,810, assigned to the assignee of the present invention. These spreader-feeder machines typically include a continuous moving feed conveyor on which the sheets are automatically laid with their leading edges perpendicular to the conveyor belts. In order to position the sheet for placement onto the conveyor, a pair of spreading clamps grip opposing top corners of the sheet. A user manually inserts the corners into the clamps. The spreading clamps are then moved apart by one or more endless belts or cables to spread the sheet. Once the sheet is spread, the spreading clamps release the corners of the sheet, and the upper portion of the sheet is forced onto the conveyor. The conveyor then advances the sheet to the ironer or other processing equipment.
One disadvantage of many spreader-feeder machines is the time required for the operator to isolate the corners of the sheet and load these corners into the clamps. A spreader-feeder disclosed in U.S. Pat. No. 5,515,627, assigned to the assignee of the present invention, overcomes this disadvantage. The user merely isolates an edge and feeds the edge in between pinch rollers. The spreader-feeder machine then isolates the corners and spreads the sheet.
The exit conveyor of the spreader-feeder machine passes the articles of laundry to one of a flatwork ironer or an automatic folder. An exit conveyor of the flatwork ironer may pass the articles of laundry to an automatic folder. An automatic separator machine may pass articles of laundry to the spreader-feeder. Each subsequent automatic laundry station operates at a similar or faster conveyance speed than the previous automatic laundry station. The difference in speeds prevents the front portion of an article of laundry from bunching or being wrinkled by passing from a faster conveyor to a slower conveyor (i.e. the article of laundry instead passes to a conveyor of a same or increased speed). However, these speed requirements may prevent one or more of the automatic laundry stations from operating a quickly as possible. Delays at one station introduce gaps between the articles of laundry conveyed between stations, resulting in inefficient use of the subsequent stations.
Exit conveyors passing articles of laundry to laundry operators rather than another station may include sensors for detecting the presence of an article of laundry on the conveyor. If an article of laundry is not present at a certain position, then the conveyor is slowed to provide extra time for the laundry operator to deal with laundry at the end of the conveyor. Similarly, where a station looses an article of laundry, an exit conveyor may be slowed to prevent a large gap between a previously exited article of laundry and the next article of laundry. However, this slow down results in even larger gaps being provided between another downstream pair of articles of laundry.
Another exit conveyor passes article of laundry to operators after separation. To provide articles of laundry to an operator more efficiently, the presence of an article is determined. If an article is not present on an exit conveyor due to an operator removing the article, the conveyor is accelerated to provide the next article to the operator more quickly.